The Truth About Open vs. Locked Differentials
Posted by Summit 4X4 on 3rd Oct 2019
Do I Need Differential Lockers?
Truth to be told is; even though not everybody needs differential lockers, everybody could use them at some point when off-roading. Most stock 4X4 vehicles come stock equipped with open differentials (Wrangler Rubicons, e-locker Toyotas and some other models will come with lockers as a factory option). What this means is that if you don’t have lockers, you truly only have 2 wheels providing traction to the vehicle at any given time when 4WD is engaged; one for the front axle and one for the rear axle. Let me tell you about how most differentials work. Differentials take the torque coming from the transmission through the driveshafts and transfer it to the wheels. This being said, the differentials get their name from the mechanism that disconnects the wheel with the most resistance so you can turn with ease and without skipping tires. The video below explains how most differentials work.
[embed]https://www.youtube.com/watch?v=yYAw79386WI[/embed]
A differential locker can make a world of difference when it comes to driving off-road. If any of your tires come slightly off the ground, all the traction from that axle is going to go to that tire (the one with the least resistance) and the tire that is actually making contact with the ground will have zero traction going to it. That, my friend, is exactly how you get stuck…even if you have a 4X4 vehicle.
Now, if you came to the same situation on a 4X4 vehicle equipped with differential lockers, as soon as your tire starts spinning off the ground you can activate your locker (if selectable or if you have an automatic locker it will activate by itself). Then the locker will lock both tires together and the one that is making contact with the ground will get the traction needed to go over the obstacle or get your vehicle un-stuck from softer ground.
Now it is time to talk about the different kind of differential lockers you can get for your vehicle.
Limited Slip Differential: This style of differential will automatically send some traction to the other tire once it feels one tire is slipping. Does not provide a 100% lock and it is recommended for mild off-road, daily drivers, towing vehicles, etc. Some examples are TrueTrac, Toyota LSD, amongst others. Automatic Lockers: This style will always provide a 100% lock while allowing the tires to spin at a different speed when turning on a corner in order to allow for a smoother driving experience on the road. This units will lock by themselves without the need for operator input. Some examples are Detroit, Aussie Locker, Lock-Rite, etc. Great for off-road vehicles, not so good for on-road vehicles, specially if there is snow or ice present. Selectable Lockers: This is the locker that is the most recommended since you can jump from an open differential to a fully locked one with the flip of a switch or the pull of a cable. These units provide 100% lock and will disengage completely so, driving would be exactly the same as driving a vehicle with open differentials but having that on-demand locking option is great! These are the most expensive kind of lockers but they are worth every penny. Rubicon wranglers and E-Locker equipped Toyotas will offer this option from the factory for either the rear axle or both axles. Electronic lockers, Air lockers and Cable Lockers fall under this category. Great for any kind of vehicle. Spools: These will keep both tires locked 100% all the time. There is no mechanism for it to lock and unlock. Both axle shafts will move as one. Not for on-road vehicles, only recommended for off-road ONLY vehicles equipped for extreme rock crawling or any kind of desert racing. Cheapest way to lock your differentials since welding your spider gears together is NEVER recommended.If you are still not sure what kind of locker is the best for your application, please give us a call 928-227-2026 or stop by the shop and we would be happy to answer all your questions and/or schedule your rig to get some lockers installed.